Bodies of water, such as lakes, ponds, canals, pools, and the like suffer from the growth of algae and other undesirable aquatic biota that lead to the depletion of oxygen and other elements required to sustain life therein. In nature, air is generally absorbed in a body of water through the agitation of surface waters resulting from waves and wind. Smaller bodies of water in stagnant areas often do not have this resource and as a result, the life forms living in such bodies of water often succumb to the absence of oxygen or relocate to other more oxygenated areas.
Apparatus for introducing a gas into a liquid is known in the art. Numerous inventors have proposed solutions to these problems. Many of these solutions utilize bubbling aeration pumps or require the use of a plurality of liquid pumps to aerate the water. As discussed more fully below, such systems are inefficient and subject to malfunction.
For example, U.S. Pat. No. 4,210,534 to Molvar discloses a system of mixing a gas with wastewater wherein the gas is injected, under pressure, into the water in a mixing chamber, where it is then discharged. This system requires a pump for the wastewater and an additional pump for pressurizing the air for injection. In addition, the air/wastewater mixture is exited through a tapered exit cylinder wherein the velocity of the mixture is increased.
U.S. Pat. No. 4,308,138 to Woltman describes a method wherein the water passes through a venturi thereby increasing water velocity and further passing through a barrel that acts as an exit chamber. Air is pulled under vacuum introduced into the water stream. The stream of water passes through the barrel; however, it does not come into contact with the sides of the barrel. The barrel then gradually opens where the air is further mixed with the water before it exists the system. This system does not create sufficient suction to saturate the water with air due to the taper nature of the entrance to the exit cylinder. A further drawback to this system is that cavitation does not occur in the exit cylinder. This is because the water/air mixture passing through the barrel does not substantially come into contact with the walls of the exit cylinder.
U.S. Pat No. 4,936,552 to Rothrock utilizes flowing water upstream of a reducing means to create a vacuum thereby pulling ambient air from the atmosphere and introducing it into the flowing wastewater stream. While this system is capable of partial aeration, it cannot attain oxygen levels sufficient to provide the desired results in a lake, pond, canal, pool or the like.
U.S. Pat. No. 6,398,194 to Tsai et al. discloses a water-pressure type aeration device utilizing a powerful water pump, which moves water through a distribution head to a plurality of cavitation housings. The plurality cavitation housings are further in fluid communication with surface air. Where water passes into the cavitation housings, it decreases the pressure therein and pulls a vacuum which, in turn, pulls air from the surface. The air is mixed with water wherein it is then expelled from the apparatus through a downward inclined guide element. All of the aforementioned aeration systems suffer from certain shortcomings, some more serious than others. For example, some require the use of more than one pump or moreover, require the use of more than one type of pump. Any of the deficiencies suffered by these devices can result in losses in efficiency and ultimately result in economic losses. Accordingly, the following disclosure describes improvements in the art of water aeration.
All documents and publications cited herein are incorporated by reference in their entirety, to the extent not inconsistent with the explicit teachings set forth herein.